Clinical efficacy of istradefylline (KW-6002) in Parkinson's disease: a randomized, controlled study.

Abstract

The objectives of this study were to evaluate the efficacy of istradefylline at an oral dose of 20 mg or 40 mg once daily for 12 weeks in Parkinson's disease (PD) patients with motor complications on levodopa therapy based on the change in the daily OFF time compared with placebo and to assess the safety at these doses. A total of 363 subjects were randomly assigned to receive 20 mg/day istradefylline (n = 119), 40 mg/day istradefylline (n = 125), or placebo (n = 119). The primary outcome variable was the change from baseline at endpoint in daily OFF time based on patients' ON/OFF diaries. At endpoint, the daily OFF time reduced from baseline by 1.31 hours for 20 mg/day istradefylline (P = 0.013 as compared to the placebo), 1.58 hours for 40 mg/day istradefylline (P < 0.001), and 0.66 hours for placebo; istradefylline significantly reduced the daily OFF time compared with placebo. The UPDRS Part III subscale score (ON state) reduced by 5.7 at endpoint in both istradefylline groups and 3.7 in the placebo group (P = 0.006 for 20 mg/day and P = 0.006 for 40 mg/day group as compared with placebo). The most commonly reported drug-related treatment emergent adverse event (TEAE) was dyskinesia, which occurred in 2.5% (3/119) of subjects receiving placebo, 8.5% (10/118) receiving 20 mg/day istradefylline, and 6.4% (8/125) receiving 40 mg/day istradefylline. We conclude that istradefylline at 20 mg and 40 mg once daily is effective in relieving wearing-off fluctuations of PD patients. In addition, istradefylline was well tolerated at both doses.

• Authors: Yoshikuni Mizuno, Kazuko Hasegawa, Tomoyoshi Kondo, Sadako Kuno, Mitsutoshi Yamamoto, Japanese Istradefylline Study Group
• Journal: Movement disorders : official journal of the Movement Disorder Society (Mov Disord) Vol. 25 Issue 10 Pg. 1437-43 (Jul 30 2010) ISSN: 1531-8257 [Electronic] United States
• PMID: 20629136 (Publication Type: Journal Article, Randomized Controlled Trial, Research Support, Non-U.S. Gov't)
• Copyright: (c) 2010 Movement Disorder Society.

Chemical References

• Purinergic P1 Receptor Antagonists
• Purines
• istradefylline

Topics

• Aged
• Analysis of Variance
• Dose-Response Relationship, Drug
• Double-Blind Method
• Female
• Humans
• Male
• Middle Aged
• Parkinson Disease (drug therapy)
• Purinergic P1 Receptor Antagonists (therapeutic use)
• Purines (therapeutic use)
• Retrospective Studies
• Severity of Illness Index
• Treatment Outcome